FIG. 1 illustrates a single plastic bottle log H as ejected from a blow molding machine with tail flash removed. The log H includes a neck I located on an axis offset D to one side of the bottle. A moil or blow dome J extends away from the neck I. Neck flash K extends from the sides of the bottle, neck, and blow dome. The neck flash is formed at the parting lines of the molds adjacent the bottle neck and is located in a common plane extending through the neck axis and parallel to the drawing sheet as seen in FIG. 1. The neck flash K and the blow dome J must be trimmed away.
Conventional blow dome trimmers linearly index a lead bottle of a series of bottles to a stationary punching station where the bottle is held stationary while the flash is trimmed away. After trimming, the bottle is released, moved downstream and a new bottle is indexed to the station.
A blow dome is conventionally trimmed from the neck of a blow molded bottle by rotating the bottle and moving the neck along a cutter which severs the blow dome from the neck. Alternatively, the blow dome may be cut away by a guillotine type blade.
Fiorani et al. U.S. Pat. No. 7,441,486, owned by the owner of this application, discloses a rotary trimmer that has a flash station to trim flash and a blow dome station to trim the blow dome from blow-molded plastic bottle logs. Fiorani et al. U.S. Pat. No. 7,441,486 is incorporated by reference into this specification as if fully set forth herein.
At the time the invention disclosed herein was made, the applicants were subject to an obligation of assigning the invention disclosed herein to the owner of U.S. Pat. No. 7,411,486. The applicants have assigned the invention to the same owner of U.S. Pat. No. 7,411,486.
The flash station wheel 24 continuously rotates about a horizontal axis as indicated by the curved arrow adjacent the wheel 24 in FIG. 13. A number of mounting plates are carried on the outside of the wheel. Each mounting plate carries a nest or log holder 98 and a set of flash punch tooling 112. The tooling set is associated with the log holder and includes a flash punch assembly. The flash punch assembly holds punches that pass through the flash to trim the flash away from a log carried in the associated log holder.
FIGS. 13 and 14 are copied from FIGS. 5 and 12 respectively of the '486 patent. References numbers and letters shown in FIGS. 13 and 14 are described in the '486 patent. FIGS. 13 and 14 illustrate a rotary trimmer 10 for trimming plastic bottle logs ejected from a blow molding machine. An infeed conveyor 32 supplies untrimmed logs to the trimmer 10, and a discharge conveyor 34 removes trimmed logs from the trimmer 10. The trimmer 10 includes a neck flash trim wheel 24 at the flash station and a spin trim wheel 28 at the blow dome station. An infeed star wheel 22 transfers blow-molded plastic bottle logs from the infeed conveyor 32 to the neck flash trim wheel 24. An intermediate star wheel 26 transfers the logs from the neck flash trim wheel 24 to the spin trim wheel 28. A discharge star wheel 30 transfers logs from the spin trim wheel 28 to the discharge conveyor 34.
The spin station wheel 28 rotates about a parallel horizontal axis. A number of log holders are carried on the outside of the wheel. The log holders are themselves rotatable about an axis and spin the logs about the neck axis. The blow domes are spun against a stationary knife extending partially around the wheel axis to trim the blow dome from the bottle neck.
The rotary trimmer forms a high-speed production line that receives untrimmed plastic logs from a blow molding machine and continuously moves the logs along the production line for removing flash and trimming blow domes.
It would be advantageous if the flash station could be modified to enable flash and the blow dome to be trimmed at a single station. Further, it would be advantageous if the blow dome is removed using a guillotine-type blade. Some blow domes are too thin to be trimmed by spin trimming.